The influence of hay steaming on clinical signs and airway immune response in severe asthmatic horses.

BACKGROUND: Avoidance of antigenic stimuli was found to significantly reverse airway obstruction of horses with severe equine asthma (sEA). To date, no published study investigated the influence of steaming hay on lower airway condition of sEA-affected horses. The objectives were to determine the clinical, cytological and cytokine respiratory responses of both sEA and control (CTL) horses experimentally exposed to steamed or dry hay. RESULTS: A cohort of 6 sEA horses and 6 CTL horses was involved in this field study. On day 0, both groups were fed with steamed hay for 5 consecutive days, followed by a wash-out period of 26 days prior to be fed with dry hay for 5 consecutive days. Investigations performed 2 days prior to and 5 days after each challenge included clinical score, tracheal mucus accumulation, and bronchoalveolar lavage fluid (BALF) cytology and cytokine mRNA expression. Feeding steamed hay significantly decreased its mould content (P < 0.001). Mucus score significantly increased when feeding dry hay (P = 0.01). No significant influence of challenge type was found on clinical score. Percentages of neutrophils (P < 0.001) as well as mRNA expression of IL-1ß (P = 0.024), IL-6R (P = 0.021), IL-18 (P = 0.009) and IL-23 (P = 0.036) in BALF of sEA affected horses were significantly increased after both (steamed and dry hay) challenges. Relative mRNA expression of IL-1ß, IL-6R and IL-23 in BALF were also significantly correlated to neutrophil percentages and both clinical and tracheal mucus score. CONCLUSIONS: Steaming significantly decreased mould content but inconsistently influenced the respiratory response of sEA affected horses when fed hay. Based on BALF cytology and cytokine profiles, its relevance might be controversial as a non-medicinal therapy for sEA-affected horses.

Surgical removal of a gastric trichophytobezoar in a foal.

This report describes a rare case of gastric impaction caused by a trichophytobezoar in a foal. This case highlights the difficulty in diagnosing this condition and reports surgical removal via a gastrotomy after failure of medical treatment.

Ablation chirurgicale d'un trichophytobézoar gastrique chez un poulain. Ce rapport décrit un rare cas d'obstruction gastrique causé par un trichophytobézoar chez un poulain. Ce cas souligne la difficulté à diagnostiquer cette affection et fait rapport sur l'ablation chirurgicale lors d'une gastrotomie après l'échec du traitement médical.(Traduit par Isabelle Vallières).

Influence of detomidine and xylazine on spleen dimensions and on splenic response to epinephrine infusion in healthy adult horses.

OBJECTIVE: To compare the changes in splenic length and thickness and in packed cell volume (PCV) following detomidine or xylazine administration and subsequent epinephrine infusion. HYPOTHESIS: Spleen relaxation occurs following xylazine or detomidine administration and interferes with subsequent splenic contractile response to epinephrine. STUDY DESIGN: Randomized non-blinded crossover experimental study. ANIMALS: 6 healthy adult mares. METHODS: The mares received an intravenous (IV) epinephrine infusion (1 µg kg(-1 ) minute(-1) over 5 minutes) one hour after IV administration of detomidine (0.01 mg kg(-1) ), xylazine (0.5 mg kg(-1) ) or no drug (control), with a withdrawal period of at least 7 days between experiments. The splenic length measured in two different axes, the splenic thickness, and the PCV were measured prior to sedation (T0), 30 minutes later, and at 5-minute intervals from the start of the epinephrine infusion (T1) until T1 + 40 minutes. Changes from base-line and between treatments were compared using a two-way anova for repeated measures. Significance was set at p < 0.05. RESULTS: Splenic length was significantly increased and PCV was significantly decreased after detomidine administration compared to baseline. Epinephrine infusion resulted in a significant decrease in splenic length and thickness, and a significant increase in PCV, irrespective of prior treatment with detomidine or xylazine. CONCLUSIONS: Detomidine administration was followed by a sonographically detectable increase of splenic length. Neither detomidine nor xylazine interfered with the ability of the spleen to contract following subsequent administration of an epinephrine infusion given one hour later. CLINICAL RELEVANCE: Previous sedation with alpha-2 agonists does not preclude the efficiency of epinephrine as a medical treatment of left dorsal displacement of the large colon, but further investigations are required with other drug doses and different time intervals between administrations.